[SC3028] When using if [ ! -z "${BASH_VERSION+x}" ] don't warn of using bash features like set -o pipefail or BASH_SOURCE

[SamuelMarks]

For bugs

• Rule Id (if any, e.g. SC1000): SC3028
• My shellcheck version (shellcheck --version or "online"): 0.10.0
• The rule's wiki page does not already cover this (e.g. https://shellcheck.net/wiki/SC2086)
• I tried on https://www.shellcheck.net/ and verified that this is still a problem on the latest commit

For new checks and feature suggestions

• https://www.shellcheck.net/ (i.e. the latest commit) currently gives no useful warnings about this
• I searched through https://github.com/koalaman/shellcheck/issues and didn't find anything related

Here's a snippet or screenshot that shows the problem:

#!/bin/sh

if [ -n "${BASH_VERSION}" ]; then
  # shellcheck disable=SC3028 disable=SC3054
  this_file="${BASH_SOURCE[0]}"
elif [ -n "${ZSH_VERSION}" ]; then
  # shellcheck disable=SC2296
  this_file="${(%):-%x}"
else
  this_file="${0}"
fi

Here's what shellcheck currently says:

When I remove the comments it says:

In POSIX sh, BASH_SOURCE is undefined.
See SC3028.
In POSIX sh, array references are undefined.
See SC3054.

Here's what I wanted or expected to see:

No error

FYI: Similar errors occur with pipefail:

In POSIX sh, set option pipefail is undefined.
See SC3040.

[brother]

Just to make it clear.
The example should be if [ -n "${BASH_VERSION}" ]; then? The title makes me believe it should be something else.

[SamuelMarks]

@brother This is my actual project with relevant line highlighted https://github.com/SamuelMarks/deploy-sh/blob/7b03f64/install.sh#L6

As you can see I've had to include a large number of # shellcheck disable 🤦

[brother]

That doesn't answer my question.
The title of the issue and the code example differs. It's hard to follow.

I don't really see how shellcheck could behave different. You asked it to use sh/posix mode and then check one variable and want another one to be included too?

[SamuelMarks]

@brother Removed the ambiguity from the issue title.

Basically if I have an if check to see if I'm in Bash then I want to be able to use Bash features without using # shellcheck disable everywhere.